A lowering of population of any species, allows for more available resources, thus higher birth recruitment rates. I hear this a lot when people are discussing coyotes like it’s some type of superpower, but it’s true for most every other species.

For example, an area with a healthy population of deer, will have available browse all year, and you’re most likely see most does giving birth to twin fawns. In an area with a lot of deer, and little available browse, there is a lot of competition for that food, does wont be as healthy and will likely have only one or no fawns. This allows the population to drop back down a touch and let food resources catch up.

Rabbits and hares are a great example of cyclical populations, where your going to have several years of increasing populations, followed by a sudden population crash. In turn, you can watch lynx populations follow a similar curve, but a year or two after the snowshoe hares.